Text processing computer applications, such as word processor arid email applications, use grammar-checking modules. A grammar checking module tests a sentence of text for errors or deviations from simple grammar rules for a particular language being used.
There is a desire to improve German language grammar checkers so that the grammar checker can detect errors in case endings of subjects, direct objects and indirect objects in verbal phrases. However, with the German language, difficult problems are encountered in any attempt to check for errors in case endings of subjects, direct objects and indirect objects.
The problem of detecting German case ending errors is much more complex than a writer's task in selecting correct case endings because the grammar checker does not have access to the writer's intended meaning. When presented with a sentence or phrase that has an error in a case ending, the grammar checker does not have access to the intended meaning of a sentence or phrase to help ascertain which case was intended for each noun phrase. German sentence word order is variable, and provides only a little information concerning likely grammatical cases of noun phrases.
The grammar checking problem is also more complex because German case endings are not unique to a particular grammatical case. For articles, adjectives or nouns, the same case ending may be used for different cases depending on a complex combination of grammatical gender, whether a noun is singular or plural, or whether a “der” type word or an “ein” type determiner word precedes the adjective. Thus, case endings do not always reliably or uniquely predict the grammatical case of a noun phrase. There is a substantial problem in presenting a user with proposed case ending corrections with so much ambiguity in the available information, and so many possible combinations of grammatically correct proposed corrections when the writer's meaning is unknown.
A grammar checking module for text processing applications is needed to provide the desired checking of grammatical case ending of subjects, direct objects and indirect objects in German language phrases.